BMW i3: Cheap, mass-produced carbon fiber cars finally come of age

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The just-announced BMW i3 could be a breakthrough for carbon fiber production as well as for electric drive. Carbon fiber reinforced plastic (CFRP) provides the weight reduction that effectively neutralizes the heft of the car’s battery pack. To make it happen, BMW teamed up with Boeing for expertise on carbon fiber manufacturing. As in the early days of the industrial revolution, BMW even sited one of the carbon fiber textile facilities near a stream for power. The result is a four-passenger car that can go 100 miles on a charge or accelerate to 60 mph in less than 7 seconds, yet weigh only 2,700 pounds (1224 kg).

BMW will be producing the first passenger car using significant amounts of carbon fiber in a vehicle designed for production of tens of thousands of units a year with no significant cost premium (over what BMW already gets for being BMW). Many automakers including BMW have made roof or hood panels from carbon fiber, mostly for limited production performance models. There are also million-dollar McLarens and Lamborghinis with CFRP bodies. Here, all the body panels are of carbon fiber and the car costs less than $50,000.

“With the BMW i3, we get a reduction of 250-350 kilos [550-770 pounds] from carbon fiber,” says Daniel Schafter, head of production of Concept BMW I, “and that more or less compensates for the weight of the battery.”

BMW’s multi-location carbon fiber production

One of BMW’s goals was to make lifecycle energy costs be less than for a traditional vehicle. Rather than farm out the carbon fiber R&D and production to others, BMW opted to retain control, much as earlier automakers started with shiploads of iron ore rather than prestamped body panels from a parts supplier. BMW and SGL Automotive Carbon Fibers set up a new factory in Moses Lake, WA. If not technically sited directly on an Industrial Revolution stream with a water wheel driving a long shaft, the Moses Lake plant draws from utilities making heavy use of hydro power.

The factory takes a polyacrylonitrile (PAN) precursor created in Otake, Japan, by another JV involving Mitsubishi Rayon (MRC) and SGL Group. Moses Lake turns the polyacrylic fibers into carbon fibers. The PAN filaments are baked at 450 degrees, turning golden brown then black. Then they’re carbonized in two more oven steps, at 1,300 degrees and 2,550 degrees. Each step is controlled to prevent the filaments from catching fire or burning; inert nitrogen gas is injected into the carbonization ovens.

The next step turns them into lightweight carbon fiber fabrics in Wackersdorf, Germany, about 100 miles from BMW’s Munich headquarters. Here, they resemble fabrics, and BMW has actually joined Germany’s textile makers alliance. There, they go to a BMW plant in Landshut, Germany for further processing, and finally, they wind up in Leipzig in eastern Germany, where the CFRP parts are finished and the i3 is assembled along with BMW’s 1 Series sedan and X1 SUV. The first cars go to the European market; the US gets in on a second wave, starting spring 2014.

I do think it is lost on many people that the Carbon Fiber and Aluminum chassis will find their way into other BMW models to make them lighter and have better performance.

A modern EV that comes in at $2700 pounds is amazing…

Bill Howard

If BMW can get a jump of 1, 3, 5 years on the competition building carbon fiber panels into mainstream cars, it’s a huge advantage. They could also go to plastic for lowly stressed parts (the decklid) or as the story notes, use chopped fiber that has 1/3 less strength but lower mfg cost. Some of the process steps BMW is using take minutes where older techniques took hours.

I have owned two old, used cars that weighed less than 2500 pounds, a VW Beetle that was not a paragon of safety, and a Mini Cooper knockoff Fiat 128 that got lighter each year through a Fiat technology called rust perforation.

Phil

So they ‘minimize energy costs’ by doing cute things like putting the carbon fiber factory near a lake…

And then they ship that carbon fiber across the globe to assemble it.

That’s called a gimmick.

Bill Howard

The light carbon fiber material gets shipped to Europe where they get produced into the body panels that become heavier (resin injection in the molding) and bulkier.BMW agrees the energy expenditure in creating the CRFP panels is more than for a metal body car. BMW says the total lifecycle costs including fuel (electricity) to run the car and what you get back when the car is recycled a decade or so from now, that will be lower.

Lower hanging fruit might be to wonder why the PRC buys scrap iron from the US, re-refines it over there, and sends it back to us as new steel. (Part of the answer may be you have more empty hulls going west across the Pacific once they’ve dropped off their loads of furniture, TVs, cars, etcetera, so why not.)

Phil

The shipping industry is pretty baffling in its mammoth size.

jfreed27

Agreed. Greenwashing with a ‘happy face’

Nic Phillips

It’s not “CHEAP” carbon fiber, it’s INEXPENSIVE

Steve Hawken

The most important points and USB of these cars are its light weight and fuel efficiency. The chassis of these cars would be very lighter and hence will give a better control for the drivers and will also save a lot on the weight and at the same time wouldn’t compo on the safety as these cars with Carbon Fiber or Aluminum body are stronger then its predecessors and also comes at lower price. That is why most of the car makers are replacing the body with this new tech.http://www.euroautomotive.net/

jfreed27

Amory Lovins touts carbon fibre as the next giant step in lower oil use. Glad to see it is coming to market.

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